US20100068441A1 - Easy-to-straight-tear plastic film, and its production method and apparatus - Google Patents
Easy-to-straight-tear plastic film, and its production method and apparatus Download PDFInfo
- Publication number
- US20100068441A1 US20100068441A1 US12/594,506 US59450608A US2010068441A1 US 20100068441 A1 US20100068441 A1 US 20100068441A1 US 59450608 A US59450608 A US 59450608A US 2010068441 A1 US2010068441 A1 US 2010068441A1
- Authority
- US
- United States
- Prior art keywords
- plastic film
- roll
- cutter
- straight
- easy
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B26—HAND CUTTING TOOLS; CUTTING; SEVERING
- B26D—CUTTING; DETAILS COMMON TO MACHINES FOR PERFORATING, PUNCHING, CUTTING-OUT, STAMPING-OUT OR SEVERING
- B26D1/00—Cutting through work characterised by the nature or movement of the cutting member or particular materials not otherwise provided for; Apparatus or machines therefor; Cutting members therefor
- B26D1/01—Cutting through work characterised by the nature or movement of the cutting member or particular materials not otherwise provided for; Apparatus or machines therefor; Cutting members therefor involving a cutting member which does not travel with the work
- B26D1/02—Cutting through work characterised by the nature or movement of the cutting member or particular materials not otherwise provided for; Apparatus or machines therefor; Cutting members therefor involving a cutting member which does not travel with the work having a stationary cutting member
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65D—CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES
- B65D65/00—Wrappers or flexible covers; Packaging materials of special type or form
- B65D65/38—Packaging materials of special type or form
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B26—HAND CUTTING TOOLS; CUTTING; SEVERING
- B26D—CUTTING; DETAILS COMMON TO MACHINES FOR PERFORATING, PUNCHING, CUTTING-OUT, STAMPING-OUT OR SEVERING
- B26D3/00—Cutting work characterised by the nature of the cut made; Apparatus therefor
- B26D3/08—Making a superficial cut in the surface of the work without removal of material, e.g. scoring, incising
- B26D3/085—On sheet material
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B26—HAND CUTTING TOOLS; CUTTING; SEVERING
- B26D—CUTTING; DETAILS COMMON TO MACHINES FOR PERFORATING, PUNCHING, CUTTING-OUT, STAMPING-OUT OR SEVERING
- B26D7/00—Details of apparatus for cutting, cutting-out, stamping-out, punching, perforating, or severing by means other than cutting
- B26D7/20—Cutting beds
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C59/00—Surface shaping of articles, e.g. embossing; Apparatus therefor
- B29C59/007—Forming single grooves or ribs, e.g. tear lines, weak spots
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C59/00—Surface shaping of articles, e.g. embossing; Apparatus therefor
- B29C59/02—Surface shaping of articles, e.g. embossing; Apparatus therefor by mechanical means, e.g. pressing
- B29C59/04—Surface shaping of articles, e.g. embossing; Apparatus therefor by mechanical means, e.g. pressing using rollers or endless belts
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B26—HAND CUTTING TOOLS; CUTTING; SEVERING
- B26D—CUTTING; DETAILS COMMON TO MACHINES FOR PERFORATING, PUNCHING, CUTTING-OUT, STAMPING-OUT OR SEVERING
- B26D7/00—Details of apparatus for cutting, cutting-out, stamping-out, punching, perforating, or severing by means other than cutting
- B26D7/20—Cutting beds
- B26D2007/202—Rollers or cylinders being pivoted during operation
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
- B29L2007/00—Flat articles, e.g. films or sheets
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
- B29L2009/00—Layered products
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/15—Sheet, web, or layer weakened to permit separation through thickness
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T83/00—Cutting
- Y10T83/04—Processes
- Y10T83/0448—With subsequent handling [i.e., of product]
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T83/00—Cutting
- Y10T83/788—Tool pair comprises rotatable anvil and fixed-type tool
Definitions
- the present invention relates to a plastic film having excellent straight tearability, and a method and an apparatus for producing such an easy-to-straight-tear plastic film at low cost without generating dust, particularly to a plastic film having straight tearability in a width direction and its production method and apparatus.
- JP 5-42951 A proposes an easy-to-open bag provided with linear dents in heat-sealing edge portions. As shown in FIG. 10 , the dents are formed by passing heat-sealing portions of a plastic film 100 between a vibrating ultrasonic hone 200 and a roll 300 having a linear grooves on a circular surface. However, dents formed by the plastic deformation of the plastic film 100 by the roll 300 do not have sufficient tearability.
- WO2003/091003 discloses a method for forming parallel linear scratches on a plastic film by bringing a roll having large numbers of fine projections on a circular surface into sliding contact with the plastic film under pressure.
- the plastic film provided with linear scratches can be torn straight from an arbitrary position.
- this production method suffers the generation of dust.
- an object of the present invention is to provide a plastic film having excellent straight tearability.
- Another object of the present invention is to provide a method and an apparatus for producing such an easy-to-straight-tear plastic film at low cost without generating dust.
- the inventor has found that (a) by arranging a roll having a cam axially extending on a circular surface and a cutter arranged in parallel to said roll with a gap narrower than the thickness of a plastic film, and by passing the plastic film between them with the cam nearing said cutter intermittently by the rotation of said roll, parallel half-cut lines can be formed on the plastic film without dust, and that (b) a plastic film thus provided with half-cut lines has excellent straight tearability.
- the present invention has been completed based on such finding.
- the long, easy-to-straight-tear plastic film of the present invention has large numbers of substantially parallel half-cut lines extending in a transverse direction on at least one surface.
- Said half-cut lines are preferably formed over the entire surface, such that the plastic film can be torn substantially straight from an arbitrary position.
- the depth of said half-cut lines is preferably 10-50% of the thickness of the plastic film.
- the method of the present invention for producing a long, easy-to-straight-tear plastic film having large numbers of substantially parallel half-cut lines extending in a transverse direction on at least one surface comprises the steps of (1) arranging a roll having at least one cam axially extending on a circular surface of said roll, and a cutter parallel to said roll with a gap narrower than the thickness of said plastic film, (2) moving said plastic film between said roll and said cutter in a direction perpendicular to the axial direction of said roll, and (3) rotating said roll, so that said cam intermittently pushes said plastic film to said cutter, to form half-cut lines on said plastic film.
- a gap between said cam and said cutter is preferably 10-50% of the thickness of said plastic film.
- Said half-cut lines are preferably formed on an entire surface of said plastic film.
- the peripheral speed of said roll is preferably 10-50 times the moving speed of said plastic film.
- the apparatus of the present invention for producing a long, easy-to-straight-tear plastic film having large numbers of substantially parallel half-cut lines extending in a transverse direction on at least one surface comprises (a) a roll having at least one cam axially extending on a circular surface of said roll, and (b) a cutter arranged in parallel to said roll with a gap narrower than the thickness of said plastic film, the rotation of said roll causing said cam to intermittently push said plastic film to said cutter to form half-cut lines on said plastic film.
- Said roll preferably has pluralities of cams with substantially equal intervals.
- a gap between said cam and said cutter is preferably 10-50% of the thickness of said plastic film.
- a holder of said cutter is fixed to a resilient plate mounted to a frame of the apparatus, and that said roll engages pluralities of actuators fixed to said frame.
- said actuators are preferably operated to press said holder, said resilient plate is resiliently deformed by a pressing force to finely adjust the position of said cutter fixed to said holder, such that a gap between said cam and said cutter is substantially uniform over the entire width of said plastic film.
- Said resilient plate preferably has a resiliently deformable thin portion.
- FIG. 1( a ) is a schematic cross-sectional view showing a plastic film before pressed by a cam of a roll.
- FIG. 1( b ) is a schematic cross-sectional view showing a plastic film pressed by a cam of a roll to come to contact with a cutter.
- FIG. 1( c ) is a schematic cross-sectional view showing a cam of a roll at the closest position to a cutter to form a half-cut line on a plastic film.
- FIG. 1( d ) is a schematic cross-sectional view showing a cam of a roll moving away from a cutter, so that a plastic film is separated from a cutter.
- FIG. 2 is a schematic cross-sectional view showing the apparatus of the present invention for producing an easy-to-straight-tear plastic film.
- FIG. 3 is a partially enlarged cross-sectional view showing a roll and a cutter.
- FIG. 4 is a partially enlarged exploded view showing a mechanism of mounting a cam to a roll.
- FIG. 5 is a partially enlarged exploded view showing a mechanism of mounting a cutter to a holder.
- FIG. 6 is a schematic view showing an apparatus for producing an easy-to-straight-tear plastic film according to one embodiment of the present invention.
- FIG. 7 is a schematic view showing the relation between a roll and a cutter.
- FIG. 8 is a perspective view showing the formation of half-cut lines to a plastic film.
- FIG. 9 is a schematic view showing an apparatus for producing an easy-to-straight-tear plastic film according to another embodiment of the present invention.
- FIG. 10 is a schematic view showing a conventional apparatus for producing a wrapping film.
- a rotatable roll 2 having pluralities of cams 20 and a cutter 3 are arranged with a narrower gap than the thickness of a long plastic film 1 ′.
- a gap d 1 between the cam 20 and the cutter 3 is preferably 10-50% of the thickness T of a plastic film 1 ′.
- An angle ⁇ 1 of the cutter 3 to the plastic film 1 ′ is preferably 90 ⁇ 10° , more preferably 90 ⁇ 5° .
- An edge angle ⁇ 2 of the cutter 3 is preferably 30-45° .
- the cam 20 comprises a front surface portion 20 a slanting rearward relative to the radius of the roll 2 , and a round top end 20 b closest to the cutter 3 .
- the plastic film 1 ′ is not cut apart when the cam 20 comes to contact with the plastic film 1 ′.
- the plastic film 1 ′ moves preferably in the same direction as the rotation direction of the roll.
- a ratio of the peripheral speed Vr of the roll 2 to the moving speed Vf of the plastic film 1 ′ is preferably 10-50, more preferably 20-40.
- the range of Vr/Vf is not restricted, and its upper limit, for instance, may be larger if the production speed is sacrificed.
- the moving speed Vf of the plastic film 1 ′ is preferably 10-500 m/minute, more preferably 10-300 m/minute.
- the rotation speed of the roll 2 is preferably 1,000-4,000 rpm, for instance, when the diameter of the roll 2 is 20-300 mm.
- the cam 20 is separate from the plastic film 1 ′ at a position where it is separate from the cutter 3 , but as the cam 20 nears the cutter 3 , it pushes the plastic film 1 ′ to the cutter 3 .
- the plastic film 1 ′ is provided with half-cut lines 10 .
- the rotational shaft of the roll 2 is set in parallel to the transverse direction of the plastic film 1 ′.
- the roll 2 is longer than the width of the plastic film 1 ′, so that the plastic film 1 ′ in its entire width comes to contact with the cam 20 of the roll 2 .
- the diameter D of the roll 2 is, for instance, 2-30 cm.
- the number of cams 20 mounted to the roll 2 is preferably 4 or more for productivity, though changeable depending on the diameter D of the roll 2 .
- the cams 20 may be integral with the roll 2 , they are preferably detachable as shown in FIG. 4 .
- the cam body 20 ′ has a ridge 20 a having a rectangular cross section on one surface
- a wedge member 21 engaging the cam body 20 ′ has a groove 21 a for receiving the ridge 20 a and a slanting surface 21 b
- a nut member 22 engaging the wedge member 21 has a slanting surface 22 a complimentary to the slanting surface 21 b of the wedge member 21 .
- the cam body 20 ′, the wedge member 21 and the nut member 22 are received in a groove 120 of the roll 2 .
- holders 4 , 4 ′ for fixing the cutter 3 are fixed to a resilient metal plate 6 mounted to a frame 70 of the apparatus.
- the resilient metal plate 6 may have a resiliently deformable thin portion 60 around a position at which the holders 4 , 4 ′ are mounted.
- the frame 70 is provided with a actuator 5 such as an air or hydraulic cylinder.
- a pressing means 5 b is mounted to a tip end of a shaft 5 a of the actuator 5 , and a buffer plate 50 made of rubber, etc. is attached to a surface of the pressing means 5 b.
- the holders 4 , 4 ′ for fixing the cutter 3 are combined by screws, one holder piece 4 being provided with a step 40 to which an end 30 of the cutter 3 abuts.
- FIG. 6 shows an apparatus for producing an easy-to-straight-tear plastic film according to one embodiment of the present invention.
- This apparatus has two stations for forming half-cut lines along the moving plastic film 1 ′.
- cutters 3 , 3 are arranged on both sides of the roll 2 having cams 20 .
- Each cutter 3 and the roll 2 having cams 20 are in the above-described positional relation.
- pluralities of actuators 5 are arranged along the roll 2 with substantially equal intervals. Because a plastic film 1 ′ on which half-cut lines are formed by the present invention usually has a thickness of about 10-40 ⁇ m, the depth of half-cut lines should be controlled with precision of several micron meters. However, it is extremely difficult to control a gap between the roll 2 and the cutter 3 with precision of several micron meters over the entire length of about 1 m of the roll 2 and the cutter 3 .
- the resilient metal plate 6 is preferably as thick as possible.
- the resilient metal plate 6 is as thick as about 1 cm, and the thin portion 60 has about half thickness thereof.
- pluralities of actuators 5 should be provided. Though not restrictive, the intervals of the actuators 5 may be about 10-30 cm. The operation of individual actuators 5 should be controlled such that the cutter 3 and the cam 20 have the same gap over their length.
- the plastic film 1 ′ passes two stations for forming half-cut lines with tension given by pluralities of nip rolls.
- the tension per width given by the nip roll 7 to the plastic film 1 ′ is, for instance, 0.5-10 kgf/m.
- half-cut lines 10 are formed two times on the plastic film 1 ′. Because half-cut lines 10 are formed four times in the entire apparatus, a finished, easy-to-straight-tear plastic film has extremely large numbers of half-cut lines 10 .
- the interval d of half-cut lines 10 is 1 mm when the rotation speed Vt of both rolls 2 , 2 is 2,000 rpm, and the moving speed Vf of the plastic film 1 ′ is 32 m/minute.
- the peripheral speed of the roll 2 is preferably 10-50 times the moving speed of the plastic film 1 ′.
- the width of each half-cut line 10 is slightly larger than the thickness of the cutter 3 .
- the half-cut lines 10 are slightly expanded by the cutter 3 .
- the above ratio within 10-50 times provides the minimum difference between the width of the half-cut lines 10 and the thickness of the cutter 3 , thereby avoiding the unevenness of the half-cut lines 10 and the breakage of the plastic film 1 ′.
- FIG. 9 shows the apparatus for producing an easy-to-straight-tear plastic film according to another embodiment of the present invention.
- This apparatus is the same as shown in FIG. 2 , except that a roll 2 is provided with eight cams 20 each having a curved tip surface.
- the plastic film 1 ′ is made of, for instance, polyesters, polyarylene sulfide(polyphenylene sulfide, etc.), polyamides, polyimides, polyamideimides, polyethersulfones, polyetheretherketones, polycarbonates, acrylic resins, polystyrenes, ABS resins, fluororesins, polyolefins(polyethylene, polypropylene, etc.), polyvinyl chlorides, etc.
- the plastic film 1 ′ may have large numbers of fine pores.
- the fine pores preferably have an average opening diameter of 0.5-100 ⁇ m and an average density of about 500/cm 2 or more.
- the fine pores may be formed by the method described in Japanese Patent 2063411.
- the long, easy-to-straight-tear plastic film 1 of the present invention obtained by the above method has large numbers of substantially parallel half-cut lines 10 extending in a transverse direction on at least one surface, it can be torn substantially straight from an arbitrary position.
- the half-cut lines 10 are preferably formed on the entire surface of the plastic film.
- the depth of the half-cut lines 10 is preferably 10-50% of the thickness of the easy-to-straight-tear plastic film 1 .
- a plastic film moves in a gap narrower than the thickness of the plastic film between a roll having cams and a cutter, so that the cams can intermittently push the plastic film to the cutter by the rotation of the roll, to form large numbers of parallel half-cut lines on the plastic film without dust.
- the easy-to-straight-tear plastic film thus obtained can be torn substantially straight from an arbitrary position.
- the easy-to-straight-tear plastic film of the present invention may be used for various wrapping bags for foods, medicines, lunch boxes, etc. Because wrappings of the easy-to-straight-tear plastic film can be torn straight from any positions, there is no inconvenience at all to open them. In addition, because mass-produced wrapping bags are generally heat-sealed in a transverse direction of a long plastic film, the use of the easy-to-straight-tear plastic film of the present invention having half-cut lines in a transverse direction makes it easy to open wrapping bags in parallel to heat seals. Also, the use of the easy-to-straight-tear plastic film of the present invention makes it unnecessary to attach tapes for providing opening width to wrapping bags.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- Forests & Forestry (AREA)
- Perforating, Stamping-Out Or Severing By Means Other Than Cutting (AREA)
- Shaping Of Tube Ends By Bending Or Straightening (AREA)
- Wrappers (AREA)
- Manufacture Of Macromolecular Shaped Articles (AREA)
Abstract
An apparatus for producing a long, easy-to-straight-tear plastic film having large numbers of substantially parallel half-cut lines extending in a transverse direction on at least one surface, comprising (a) a roll having at least one cam axially extending on a circular surface of said roll, and (b) a cutter arranged in parallel to said roll with a gap narrower than the thickness of said plastic film, the rotation of said roll causing said cam to intermittently push said plastic film to said cutter to form half-cut lines on said plastic film.
Description
- The present invention relates to a plastic film having excellent straight tearability, and a method and an apparatus for producing such an easy-to-straight-tear plastic film at low cost without generating dust, particularly to a plastic film having straight tearability in a width direction and its production method and apparatus.
- Various easy-to-open wrapping bags have been developed so far. For instance, JP 5-42951 A proposes an easy-to-open bag provided with linear dents in heat-sealing edge portions. As shown in
FIG. 10 , the dents are formed by passing heat-sealing portions of aplastic film 100 between a vibratingultrasonic hone 200 and aroll 300 having a linear grooves on a circular surface. However, dents formed by the plastic deformation of theplastic film 100 by theroll 300 do not have sufficient tearability. - WO2003/091003 discloses a method for forming parallel linear scratches on a plastic film by bringing a roll having large numbers of fine projections on a circular surface into sliding contact with the plastic film under pressure. The plastic film provided with linear scratches can be torn straight from an arbitrary position. However, this production method suffers the generation of dust.
- Accordingly, an object of the present invention is to provide a plastic film having excellent straight tearability.
- Another object of the present invention is to provide a method and an apparatus for producing such an easy-to-straight-tear plastic film at low cost without generating dust.
- As a result of intensive research in view of the above objects, the inventor has found that (a) by arranging a roll having a cam axially extending on a circular surface and a cutter arranged in parallel to said roll with a gap narrower than the thickness of a plastic film, and by passing the plastic film between them with the cam nearing said cutter intermittently by the rotation of said roll, parallel half-cut lines can be formed on the plastic film without dust, and that (b) a plastic film thus provided with half-cut lines has excellent straight tearability. The present invention has been completed based on such finding.
- Thus, the long, easy-to-straight-tear plastic film of the present invention has large numbers of substantially parallel half-cut lines extending in a transverse direction on at least one surface.
- Said half-cut lines are preferably formed over the entire surface, such that the plastic film can be torn substantially straight from an arbitrary position. To secure sufficient straight tearability, the depth of said half-cut lines is preferably 10-50% of the thickness of the plastic film.
- The method of the present invention for producing a long, easy-to-straight-tear plastic film having large numbers of substantially parallel half-cut lines extending in a transverse direction on at least one surface comprises the steps of (1) arranging a roll having at least one cam axially extending on a circular surface of said roll, and a cutter parallel to said roll with a gap narrower than the thickness of said plastic film, (2) moving said plastic film between said roll and said cutter in a direction perpendicular to the axial direction of said roll, and (3) rotating said roll, so that said cam intermittently pushes said plastic film to said cutter, to form half-cut lines on said plastic film.
- A gap between said cam and said cutter is preferably 10-50% of the thickness of said plastic film. Said half-cut lines are preferably formed on an entire surface of said plastic film. The peripheral speed of said roll is preferably 10-50 times the moving speed of said plastic film.
- The apparatus of the present invention for producing a long, easy-to-straight-tear plastic film having large numbers of substantially parallel half-cut lines extending in a transverse direction on at least one surface comprises (a) a roll having at least one cam axially extending on a circular surface of said roll, and (b) a cutter arranged in parallel to said roll with a gap narrower than the thickness of said plastic film, the rotation of said roll causing said cam to intermittently push said plastic film to said cutter to form half-cut lines on said plastic film.
- Said roll preferably has pluralities of cams with substantially equal intervals. A gap between said cam and said cutter is preferably 10-50% of the thickness of said plastic film.
- It is preferable that a holder of said cutter is fixed to a resilient plate mounted to a frame of the apparatus, and that said roll engages pluralities of actuators fixed to said frame. When said actuators are preferably operated to press said holder, said resilient plate is resiliently deformed by a pressing force to finely adjust the position of said cutter fixed to said holder, such that a gap between said cam and said cutter is substantially uniform over the entire width of said plastic film. Said resilient plate preferably has a resiliently deformable thin portion.
-
FIG. 1( a) is a schematic cross-sectional view showing a plastic film before pressed by a cam of a roll. -
FIG. 1( b) is a schematic cross-sectional view showing a plastic film pressed by a cam of a roll to come to contact with a cutter. -
FIG. 1( c) is a schematic cross-sectional view showing a cam of a roll at the closest position to a cutter to form a half-cut line on a plastic film. -
FIG. 1( d) is a schematic cross-sectional view showing a cam of a roll moving away from a cutter, so that a plastic film is separated from a cutter. -
FIG. 2 is a schematic cross-sectional view showing the apparatus of the present invention for producing an easy-to-straight-tear plastic film. -
FIG. 3 is a partially enlarged cross-sectional view showing a roll and a cutter. -
FIG. 4 is a partially enlarged exploded view showing a mechanism of mounting a cam to a roll. -
FIG. 5 is a partially enlarged exploded view showing a mechanism of mounting a cutter to a holder. -
FIG. 6 is a schematic view showing an apparatus for producing an easy-to-straight-tear plastic film according to one embodiment of the present invention. -
FIG. 7 is a schematic view showing the relation between a roll and a cutter. -
FIG. 8 is a perspective view showing the formation of half-cut lines to a plastic film. -
FIG. 9 is a schematic view showing an apparatus for producing an easy-to-straight-tear plastic film according to another embodiment of the present invention. -
FIG. 10 is a schematic view showing a conventional apparatus for producing a wrapping film. - [1] Method and Apparatus for Producing Easy-To-Straight-Tear Plastic Film
- As shown in
FIG. 1( a), arotatable roll 2 having pluralities ofcams 20 and acutter 3 are arranged with a narrower gap than the thickness of a longplastic film 1′. A gap d1 between thecam 20 and thecutter 3 is preferably 10-50% of the thickness T of aplastic film 1′. An angle θ1 of thecutter 3 to theplastic film 1′ is preferably 90±10° , more preferably 90±5° . An edge angle θ2 of thecutter 3 is preferably 30-45° . - The
cam 20 comprises afront surface portion 20 a slanting rearward relative to the radius of theroll 2, and a roundtop end 20 b closest to thecutter 3. With this structure, theplastic film 1′ is not cut apart when thecam 20 comes to contact with theplastic film 1′. Theplastic film 1′ moves preferably in the same direction as the rotation direction of the roll. To form sharp half-cut lines 10, a ratio of the peripheral speed Vr of theroll 2 to the moving speed Vf of theplastic film 1′ is preferably 10-50, more preferably 20-40. Of course, the range of Vr/Vf is not restricted, and its upper limit, for instance, may be larger if the production speed is sacrificed. To obtain such a Vr/Vf ratio, the moving speed Vf of theplastic film 1′ is preferably 10-500 m/minute, more preferably 10-300 m/minute. The rotation speed of theroll 2 is preferably 1,000-4,000 rpm, for instance, when the diameter of theroll 2 is 20-300 mm. - As shown in
FIGS. 1( a) to 1(d), thecam 20 is separate from theplastic film 1′ at a position where it is separate from thecutter 3, but as thecam 20 nears thecutter 3, it pushes theplastic film 1′ to thecutter 3. At the closest position shown inFIG. 1( c), theplastic film 1′ is provided with half-cut lines 10. - As shown in
FIGS. 2 and 3 , the rotational shaft of theroll 2 is set in parallel to the transverse direction of theplastic film 1′. Theroll 2 is longer than the width of theplastic film 1′, so that theplastic film 1′ in its entire width comes to contact with thecam 20 of theroll 2. The diameter D of theroll 2 is, for instance, 2-30 cm. The number ofcams 20 mounted to theroll 2 is preferably 4 or more for productivity, though changeable depending on the diameter D of theroll 2. - Although the
cams 20 may be integral with theroll 2, they are preferably detachable as shown inFIG. 4 . In this case, thecam body 20′ has aridge 20 a having a rectangular cross section on one surface, awedge member 21 engaging thecam body 20′ has agroove 21 a for receiving theridge 20 a and aslanting surface 21 b, and anut member 22 engaging thewedge member 21 has aslanting surface 22 a complimentary to theslanting surface 21 b of thewedge member 21. Thecam body 20′, thewedge member 21 and thenut member 22 are received in agroove 120 of theroll 2. When abolt 23 threadably engages a threadedhole 120 a of theroll 2 via thenut member 22, thecam body 20′ is pushed by thenut member 22 via thewedge member 21, so that two surfaces of thecam body 20′ are strongly abutted to twosurfaces groove 120, resulting in precise positioning of thecam body 20′. - As shown in
FIGS. 2 and 3 ,holders cutter 3 are fixed to aresilient metal plate 6 mounted to aframe 70 of the apparatus. Theresilient metal plate 6 may have a resiliently deformablethin portion 60 around a position at which theholders frame 70 is provided with aactuator 5 such as an air or hydraulic cylinder. Apressing means 5 b is mounted to a tip end of ashaft 5 a of theactuator 5, and abuffer plate 50 made of rubber, etc. is attached to a surface of thepressing means 5 b. As shown inFIG. 5 , theholders cutter 3 are combined by screws, oneholder piece 4 being provided with astep 40 to which anend 30 of thecutter 3 abuts. -
FIG. 6 shows an apparatus for producing an easy-to-straight-tear plastic film according to one embodiment of the present invention. This apparatus has two stations for forming half-cut lines along the movingplastic film 1′. In each station for forming half-cut lines,cutters roll 2 havingcams 20. Eachcutter 3 and theroll 2 havingcams 20 are in the above-described positional relation. - In a preferred embodiment of the present invention, as shown in
FIG. 7 , pluralities ofactuators 5 are arranged along theroll 2 with substantially equal intervals. Because aplastic film 1′ on which half-cut lines are formed by the present invention usually has a thickness of about 10-40 μm, the depth of half-cut lines should be controlled with precision of several micron meters. However, it is extremely difficult to control a gap between theroll 2 and thecutter 3 with precision of several micron meters over the entire length of about 1 m of theroll 2 and thecutter 3. Thus used is extremely small resilient deformation of theresilient metal plate 6, to which theholders cutter 3 are fixed, obtained by pushing theresilient metal plate 6 by theactuator 5, so that the position of thecutter 3 can be controlled with precision of several micron meters. Thethin portion 60 makes it possible to cause the parallel movement of theresilient metal plate 6 with a relatively small pushing force, thereby providing more precise position control of thecutter 3. To secure high positional precision of thecutter 3, theresilient metal plate 6 is preferably as thick as possible. For instance, theresilient metal plate 6 is as thick as about 1 cm, and thethin portion 60 has about half thickness thereof. - In the case of a
cutter 3 of about 1 m, for instance, because it is difficult to have a uniform gap between thecutter 3 and thecam 20 along their length, pluralities ofactuators 5 should be provided. Though not restrictive, the intervals of theactuators 5 may be about 10-30 cm. The operation ofindividual actuators 5 should be controlled such that thecutter 3 and thecam 20 have the same gap over their length. - In the apparatus shown in
FIG. 6 , theplastic film 1′ passes two stations for forming half-cut lines with tension given by pluralities of nip rolls. The tension per width given by thenip roll 7 to theplastic film 1′ is, for instance, 0.5-10 kgf/m. Because there arecutters roll 2 in each station for forming half-cut lines, as shown inFIG. 8 , half-cut lines 10 are formed two times on theplastic film 1′. Because half-cut lines 10 are formed four times in the entire apparatus, a finished, easy-to-straight-tear plastic film has extremely large numbers of half-cut lines 10. - The interval d (mm) of half-
cut lines 10, the moving speed Vf (mm/minute) of theplastic film 1′, the rotation speed Vt (rpm) of theroll 2, the number n ofrolls 2, the number m ofcams 20 in eachroll 2, and the number p ofcutters 3 per oneroll 2 meet the relation of d×n×m×p=Vf/Vt. In the apparatus shown inFIG. 6 , for instance, the interval d of half-cut lines 10 is 1 mm when the rotation speed Vt of bothrolls plastic film 1′ is 32 m/minute. - The peripheral speed of the
roll 2 is preferably 10-50 times the moving speed of theplastic film 1′. As shown inFIG. 1( c), because theplastic film 1′ is moving even while thecutter 3 bites theplastic film 1′, the width of each half-cut line 10 is slightly larger than the thickness of thecutter 3. Namely, the half-cut lines 10 are slightly expanded by thecutter 3. The above ratio within 10-50 times provides the minimum difference between the width of the half-cut lines 10 and the thickness of thecutter 3, thereby avoiding the unevenness of the half-cut lines 10 and the breakage of theplastic film 1′. -
FIG. 9 shows the apparatus for producing an easy-to-straight-tear plastic film according to another embodiment of the present invention. This apparatus is the same as shown inFIG. 2 , except that aroll 2 is provided with eightcams 20 each having a curved tip surface. - [2] Plastic Film
- The
plastic film 1′ is made of, for instance, polyesters, polyarylene sulfide(polyphenylene sulfide, etc.), polyamides, polyimides, polyamideimides, polyethersulfones, polyetheretherketones, polycarbonates, acrylic resins, polystyrenes, ABS resins, fluororesins, polyolefins(polyethylene, polypropylene, etc.), polyvinyl chlorides, etc. Theplastic film 1′ may have large numbers of fine pores. The fine pores preferably have an average opening diameter of 0.5-100 μm and an average density of about 500/cm2 or more. The fine pores may be formed by the method described in Japanese Patent 2063411. - [3] Easy-To-Straight-Tear Plastic Film
- Because the long, easy-to-straight-
tear plastic film 1 of the present invention obtained by the above method has large numbers of substantially parallel half-cut lines 10 extending in a transverse direction on at least one surface, it can be torn substantially straight from an arbitrary position. The half-cut lines 10 are preferably formed on the entire surface of the plastic film. To have high strength and straight tearability, the depth of the half-cut lines 10 is preferably 10-50% of the thickness of the easy-to-straight-tear plastic film 1. - Although the present invention has been explained above referring to the attached drawings, the present invention is not restricted thereto but may be modified unless changing its concept.
- In the present invention, a plastic film moves in a gap narrower than the thickness of the plastic film between a roll having cams and a cutter, so that the cams can intermittently push the plastic film to the cutter by the rotation of the roll, to form large numbers of parallel half-cut lines on the plastic film without dust. The easy-to-straight-tear plastic film thus obtained can be torn substantially straight from an arbitrary position.
- The easy-to-straight-tear plastic film of the present invention may be used for various wrapping bags for foods, medicines, lunch boxes, etc. Because wrappings of the easy-to-straight-tear plastic film can be torn straight from any positions, there is no inconvenience at all to open them. In addition, because mass-produced wrapping bags are generally heat-sealed in a transverse direction of a long plastic film, the use of the easy-to-straight-tear plastic film of the present invention having half-cut lines in a transverse direction makes it easy to open wrapping bags in parallel to heat seals. Also, the use of the easy-to-straight-tear plastic film of the present invention makes it unnecessary to attach tapes for providing opening width to wrapping bags.
Claims (14)
1. A long, easy-to-straight-tear plastic film having large numbers of substantially parallel half-cut lines extending in a transverse direction on at least one surface.
2. The easy-to-straight-tear plastic film according to claim 1 , wherein said half-cut lines are formed over the entire surface.
3. The easy-to-straight-tear plastic film according to claim 1 , wherein the depth of said half-cut lines is 10-50% of the thickness of said plastic film.
4. A method for producing a long, easy-to-straight-tear plastic film having large numbers of substantially parallel half-cut lines extending in a transverse direction on at least one surface, comprising the steps of (1) arranging a roll having at least one cam axially extending on a circular surface of said roll, and a cutter parallel to said roll, with a gap narrower than the thickness of said plastic film, (2) moving said plastic film between said roll and said cutter in a direction perpendicular to the axial direction of said roll, and (3) rotating said roll so that said cam intermittently pushes said plastic film to said cutter to form half-cut lines on said plastic film.
5. The method for producing an easy-to-straight-tear plastic film according to claim 4 , wherein a gap between said cam and said cutter is 10-50% of the thickness of said plastic film.
6. The method for producing an easy-to-straight-tear plastic film according to claim 4 , wherein said half-cut lines are formed on an entire surface of said plastic film.
7. The method for producing an easy-to-straight-tear plastic film according to claim 4 , wherein said roll has pluralities of cams with substantially equal intervals.
8. The method for producing an easy-to-straight-tear plastic film according to claim 4 , wherein the peripheral speed of said roll is 10-50 times the moving speed of said plastic film.
9. An apparatus for producing a long, easy-to-straight-tear plastic film having large numbers of substantially parallel half-cut lines extending in a transverse direction on at least one surface, comprising (a) a roll having at least one cam axially extending on a circular surface of said roll, and (b) a cutter arranged in parallel to said roll with a gap narrower than the thickness of said plastic film, said plastic film moving between said roll and said cutter in a direction perpendicular to the axial direction of said roll, the rotation of said roll causing said cam to intermittently push said plastic film to said cutter to form half-cut lines on said plastic film.
10. The apparatus for producing an easy-to-straight-tear plastic film according to claim 9 , wherein a gap between said cam and said cutter is 10-50% of the thickness of said plastic film.
11. The apparatus for producing an easy-to-straight-tear plastic film according to claim 9 , wherein said roll has pluralities of cams with substantially equal intervals.
12. The apparatus for producing an easy-to-straight-tear plastic film according to claim 9 , wherein a holder of said cutter is fixed to a resilient plate mounted to a frame of the apparatus, wherein said holder engages pluralities of actuators fixed to said frame along said roll, and wherein when said actuators are operated to press said holder, said resilient plate is resiliently deformed by a pressing force to finely adjust the position of said cutter fixed to said holder, such that a gap between said cam and said cutter is substantially uniform over the entire width of said plastic film.
13. The apparatus for producing an easy-to-straight-tear plastic film according to claim 9 , wherein a holder of said cutter is fixed to a resilient plate mounted to a frame of the apparatus, wherein said holder engages pluralities of actuators fixed to said frame along said roll, and wherein when said actuators are operated to press said holder, said resilient plate is resiliently deformed by a pressing force to finely adjust the position of said cutter fixed to said holder, such that a gap between said cam and said cutter is substantially uniform over the entire width of said plastic film.
14. The apparatus for producing an easy-to-straight-tear plastic film according to claim 13 , wherein said resilient plate has a resiliently deformable thin portion.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2007096880 | 2007-04-02 | ||
JP2007-096880 | 2007-04-02 | ||
PCT/JP2008/056613 WO2008120804A1 (en) | 2007-04-02 | 2008-04-02 | Linearly tearable plastic film, method and device for producing the same and |
Publications (1)
Publication Number | Publication Date |
---|---|
US20100068441A1 true US20100068441A1 (en) | 2010-03-18 |
Family
ID=39808385
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US12/594,506 Abandoned US20100068441A1 (en) | 2007-04-02 | 2008-04-02 | Easy-to-straight-tear plastic film, and its production method and apparatus |
Country Status (6)
Country | Link |
---|---|
US (1) | US20100068441A1 (en) |
JP (1) | JP4976486B2 (en) |
KR (1) | KR20100014668A (en) |
CN (1) | CN101636257B (en) |
TW (1) | TW200932498A (en) |
WO (1) | WO2008120804A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2998823A1 (en) * | 2012-11-30 | 2014-06-06 | Oberthur Technologies | Device for cutting test band utilized for support card of e.g. smart card, has support unit ready to support test band against blade, and adjustment unit to regulate play of test band with regard to blade so as to regulate depth of notch |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN117400324B (en) * | 2023-12-14 | 2024-03-08 | 山东森荣新材料股份有限公司 | Dental floss apparatus for producing |
Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4114491A (en) * | 1974-09-24 | 1978-09-19 | Hitachi Metals, Ltd. | Full rotation type paper web cutting device |
US4245538A (en) * | 1978-03-11 | 1981-01-20 | Werner Kammann Maschinenfabrik Gmbh | Process and apparatus for cutting portions out of a web of material |
US4494435A (en) * | 1983-09-23 | 1985-01-22 | Ned Lindsay | Cutting device |
US4680083A (en) * | 1984-04-13 | 1987-07-14 | Kabushiki Kaisha Sato | Cutter device for a film strip on a laminate |
US5152205A (en) * | 1990-07-26 | 1992-10-06 | Mitsubishi Jukogyo Kabushiki Kaisha | Rotary shear |
US5220858A (en) * | 1989-06-13 | 1993-06-22 | Samuel Jones & Co. Limited | Method and apparatus for forming scored lines on sheet material |
US5816993A (en) * | 1996-01-22 | 1998-10-06 | Stone Container Corporation | Apparatus and method for attaching carrying handles to bags |
US5881622A (en) * | 1995-05-26 | 1999-03-16 | Voith Sulzerpapiermaschinen Gmbh | Device for perforating a running web |
US20050233102A1 (en) * | 2002-04-25 | 2005-10-20 | Seiji Kagawa | Linearly easy-to-rupture thermoplastic resin film, and method and device for manufacturing the resin film |
US7226405B2 (en) * | 2004-01-12 | 2007-06-05 | Graphic Packaging International, Inc. | Methods and apparatus for forming a reverse kiss cut and score line in a sheet of deformable material |
US7325472B2 (en) * | 2003-01-15 | 2008-02-05 | Tokyo Automatic Machinery Works, Ltd. | Film cutting device |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2002059487A (en) * | 2000-08-14 | 2002-02-26 | Seiji Kagawa | Apparatus for manufacturing porous film |
JP4447144B2 (en) * | 2000-10-13 | 2010-04-07 | 大日本印刷株式会社 | Scratch forming roll and plastic film on which scars are formed using the roll |
JP2002224994A (en) * | 2001-01-30 | 2002-08-13 | Totani Corp | Processing device for plastic bag |
-
2008
- 2008-04-02 KR KR20097020343A patent/KR20100014668A/en not_active Application Discontinuation
- 2008-04-02 JP JP2009507558A patent/JP4976486B2/en not_active Expired - Fee Related
- 2008-04-02 WO PCT/JP2008/056613 patent/WO2008120804A1/en active Application Filing
- 2008-04-02 CN CN200880008880XA patent/CN101636257B/en not_active Expired - Fee Related
- 2008-04-02 TW TW97112106A patent/TW200932498A/en unknown
- 2008-04-02 US US12/594,506 patent/US20100068441A1/en not_active Abandoned
Patent Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4114491A (en) * | 1974-09-24 | 1978-09-19 | Hitachi Metals, Ltd. | Full rotation type paper web cutting device |
US4245538A (en) * | 1978-03-11 | 1981-01-20 | Werner Kammann Maschinenfabrik Gmbh | Process and apparatus for cutting portions out of a web of material |
US4494435A (en) * | 1983-09-23 | 1985-01-22 | Ned Lindsay | Cutting device |
US4680083A (en) * | 1984-04-13 | 1987-07-14 | Kabushiki Kaisha Sato | Cutter device for a film strip on a laminate |
US5220858A (en) * | 1989-06-13 | 1993-06-22 | Samuel Jones & Co. Limited | Method and apparatus for forming scored lines on sheet material |
US5152205A (en) * | 1990-07-26 | 1992-10-06 | Mitsubishi Jukogyo Kabushiki Kaisha | Rotary shear |
US5881622A (en) * | 1995-05-26 | 1999-03-16 | Voith Sulzerpapiermaschinen Gmbh | Device for perforating a running web |
US5816993A (en) * | 1996-01-22 | 1998-10-06 | Stone Container Corporation | Apparatus and method for attaching carrying handles to bags |
US20050233102A1 (en) * | 2002-04-25 | 2005-10-20 | Seiji Kagawa | Linearly easy-to-rupture thermoplastic resin film, and method and device for manufacturing the resin film |
US7325472B2 (en) * | 2003-01-15 | 2008-02-05 | Tokyo Automatic Machinery Works, Ltd. | Film cutting device |
US7226405B2 (en) * | 2004-01-12 | 2007-06-05 | Graphic Packaging International, Inc. | Methods and apparatus for forming a reverse kiss cut and score line in a sheet of deformable material |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2998823A1 (en) * | 2012-11-30 | 2014-06-06 | Oberthur Technologies | Device for cutting test band utilized for support card of e.g. smart card, has support unit ready to support test band against blade, and adjustment unit to regulate play of test band with regard to blade so as to regulate depth of notch |
Also Published As
Publication number | Publication date |
---|---|
TW200932498A (en) | 2009-08-01 |
CN101636257B (en) | 2012-09-05 |
JPWO2008120804A1 (en) | 2010-07-15 |
WO2008120804A1 (en) | 2008-10-09 |
CN101636257A (en) | 2010-01-27 |
JP4976486B2 (en) | 2012-07-18 |
KR20100014668A (en) | 2010-02-10 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US6908295B2 (en) | Process and apparatus for embossing precise microstructures and embossing tool for making same | |
KR101906959B1 (en) | Apparatus for forming slant, linear easy-to-tear portions on long plastic film | |
JP3799015B2 (en) | Method for manufacturing tape-shaped article | |
WO2014171365A1 (en) | Method for manufacturing thermoplastic film | |
PL1874522T3 (en) | Use of an extrusion device for producing a thermoplastic plastic film, film and use thereof | |
US9296146B1 (en) | Extrusion-to-sheet production line and method | |
JP2006327562A (en) | Method for manufacturing synthtic resin core material | |
US20100068441A1 (en) | Easy-to-straight-tear plastic film, and its production method and apparatus | |
US10744665B2 (en) | Apparatus for producing microporous plastic film | |
EP2206593B1 (en) | Simultaneous molding and decorating method | |
JP4443439B2 (en) | Braille embossing equipment | |
PT2976209T (en) | Film-embossing apparatus | |
JP6645751B2 (en) | Multi-manifold extrusion die with frame system and method of using same | |
US10940618B2 (en) | Apparatus for producing microporous plastic film | |
CN102376195A (en) | In-mold label and manufacturing method thereof | |
JP5148376B2 (en) | Injection mold and method of manufacturing resin molded product using the same | |
JP5053464B1 (en) | Equipment for forming oblique linear easy-cleavage on long plastic film | |
JP4976581B1 (en) | Easy-cleavage forming device | |
JP6040164B2 (en) | Easy-cleavage forming device | |
JPH0662153B2 (en) | Blister packaging equipment | |
JP6040165B2 (en) | Easy-cleavage forming device | |
EP1153730A4 (en) | Production method for thermoplastic polymer sheet and optical sheet | |
JP2003117982A (en) | Linear lamination processing device | |
RU2004117682A (en) | DEVICE FOR MANUFACTURING THIN PROFILE TAPES FROM THERMOPLASTES |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |